It all started so very innocently on a late Summer evening in 2014. I was sorting out my record collection and had decided to say goodbye to some of the vinyl albums that I had outgrown. Amongst the albums were five by a Dutch band called "Shocking Blue." I had been a very big fan of that band when I was younger, but my musical tastes had changed, so I listed them on eBay in a ten-day auction.

When I checked my listings the following evening, I had received a message regarding the albums from an eBay member from the Netherlands. The message read as follows.

"Hi, I am interested in buying your Shocking Blue albums. I am also interested in buying your Lone Star and Golden Earring albums. Could you please provide your phone number, so that we can discuss the matter?" Thanks, Mariska.

I sent my phone number to Mariska and within a few minutes she phoned back. Mariska told me that she lived in Amsterdam and that her favourite thing to do after work was to chill out while listening to her albums.

We had a lot in common, because I did similar things most evenings. We even used the same turntable, a Linn LP 12. We chatted for about an hour about our record collections and the various albums that I was prepared to sell.

Mariska bought thirteen albums and offered to pay by bank transfer if I ended the auction on my listed albums. She had offered me very good prices, so I was more than happy to do so. She said that she had to go back to work for two hours and would send the payment as soon as she got home, around Midnight.

I spent the next few hours cleaning and checking all the albums. Some of them hadn't been played for many years, and they had collected a lot of dust. They all got a last spin on my turntable before being put back into new anti-static sleeves.

I had just gotten into bed when my phone rang. It was almost three a.m.

"Hi Kate, it's Mariska. I have just sent you a payment, and I added thirty pounds for shipping. My apologies for phoning so late, but tonight was very busy because there's a rock festival in the City this week."

"Do you work in a bar or restaurant? I hope that you're well paid for working so late."

Mariska took a few seconds to answer, but when she did, it was me who was stuck for words.

"No, Kate, I work in neither of those. I work in De Wallen. In the windows of the red light district. I hope that I haven't shocked you, but it's normal here, and it's accepted as a regular job. You can ask me anything that you like. I don't mind talking about my job."

I told Mariska that I admired her for doing a job that I could only fantasise about doing, and said that we still have a very Victorian attitude in Northern Ireland. I had watched a documentary programme on television about the red light district, so I wasn't totally in the dark about what went on there.

"You should come to Amsterdam and see it for yourself. I could show you around, and you could deliver my records personally. You're very welcome to stay with me if you would like to?"

Mariska didn't have to ask me twice. I accepted her offer, and the very next morning, I went online to book a return flight to Amsterdam for just under seventy pounds.

My flight departed from Belfast City Airport the following Friday morning at seven thirty am and arrived at Schiphol Airport at nine am. Mariska picked me up from the Airport and she drove me to her house, which was situated in a leafy suburb, approximately three miles from Amsterdam City Centre.

As we drank coffee in her kitchen, I asked her about her work in the windows. She told me that she rented the unit for 1100 Euros per week and that it was expected to be open from ten am until six am the following day. Mariska said that when she wasn't working, she hired the window to a few other registered sex workers whom she knew well and were clean and trustworthy.

When I asked Mariska how many clients she would have sex with every day, she said,

"Kate, my dear, I never count cocks. I count the money at the end of each day, and if I have less than 1000 Euros, I am disappointed

It was obvious by looking around me that Mariska was doing well. Her house was a credit to her. It was spotless and all the fixtures and fittings were of the highest quality.

Mariska finished her coffee and told me that she would have to leave for work soon. She told me that she would be working until three pm, and I could either wait for her in the house or come into town with her to look around and maybe do some shopping.

I decided to go with Mariska, and as it was a warm day, I changed out of my travelling clothes and put on a short skirt and a white, sleeveless top.

We drove into the City and Mariska showed me the room where she worked. The floor was tiled, and the only furniture was a bed, a chair and a small wash hand basin. The room was spotless. A door at the back of the room led to a small shower and a changing room. Mariska started getting undressed, and I left her alone after promising to return at three o'clock.

The street outside wasn't very busy. Just a few people walking around and looking through the windows. Many of the windows had the curtains drawn, but the majority were occupied. Most of the women behind the glass ignored me; a few smiled or waved, and one girl who looked to be in her early twenties opened her door and called on me to come in and have some fun with her.

The red light district extended for a few streets, and then I found myself on a street with a canal on one side and market stalls on the other. There was a very loud Australian guy who was fishing for metal with a strong magnet. I'd watched some of his YouTube videos, so I crossed the street and spent a while chatting with him and his friends.

The market was more interesting. I found a stall with second-hand records and checked out every album that was for sale. I didn't buy anything, but I always live in hope of finding a rare gem...

Most of the other market stalls were selling fruit or clothing. As I approached an underwear stall, a bearded man held up a black cupless long-line bra and said, "Ten Euro, you will look very sexy in the window, wearing this."

I told him that I wasn't a window girl, but I liked the garment. After some negotiations with the man, I bought the bra, a black see-through blouse and three very sexy G-strings for twenty Euros.

I had just started making my way back to the red light district when my phone rang. It was Mariska.

"Where are you, Kate? I've had to stop early, because I have a severe toothache and my dentist has given me an emergency appointment."

I told her where I was, and a few minutes later, she picked me up. We drove to the dental surgery, where the Dentist gave her antibiotics and an appointment for the following week.

When we got back to Mariska's house, she started phoning around to find someone to stand in for her from eight pm to midnight, but had no luck.

"Well, Kate, it looks like I either drag myself back to work this evening, or my window will be closed for the first time in five years, but I don't think that I'm up to it."

"Why don't you let me stand in for you tonight? I spent a while watching the girls in the windows today, and to be honest, most of them looked less erotic than Ena Sharples. I bet that I could do better than most of them."

Mariska said that she had no idea who Ena Sharples was, so I found an image of Ena on my phone, and she burst into laughter.

"Honestly, Mariska, one of the girls was banging the window, and another was shaking like she was having a fit. If I were a man, I'd be running away. I didn't find that erotic at all. I would just sit close to the window, reading a book and smiling at anyone who looked in."

"OK, Kate, give it a try. I'm not in the mood for a debate, but only girls who are registered with the authorities are permitted to work in the windows, so your alter ego will be Katya, and you're from Poland. There are condoms in the drawer in the back room, and they must be used every time. You'll also find a box of disposable bed sheets and cleaning materials there. Change the sheet after each use and clean every surface that anyone has touched. Take my car and good luck. I'm off to bed for an hour."

I took a quick shower before driving to De Wallen. The street was a lot busier than it had been in the afternoon, and all the windows were lit up, although many of them had the curtains drawn.

I went inside and got changed into my working clothes. I put on the long-line, cupless bra and G-string that I'd bought earlier, with black stockings and high-heeled shoes. I also wore the lace top to cover my boobs while on view in the window, because it's against the rules to show boobs and pussy to the public.

I placed the chair close to the window, opened the curtains, and sat down to read. I crossed my legs to show my thighs off and waited, but I didn't have to wait long.

Four young men walked past, gave me a long look, and then stopped. They had English accents, and one of them seemed to be daring the others to knock on my door.

I put the book down, opened the door and smiled at the group of young men.

It was time to become Katya and use my fake Polish accent. Anything's better than my broad Belfast accent.

"Hello, I Katya. Maybe I help you?"

A tall guy with a Geordie accent spoke up first. He pointed to two of his group and said, "These two here are looking for a blow job."

"Is no problem. Forty Euro each, yes, no?"

Both of them agreed and came inside. I closed the door and drew the curtains. They both looked very nervous, and I was nervous too, but I forced a smile and told them, "OK, guys, Katya here to give you a good time. Pay now, please."

They gave me the fee, and I gave both of them a condom, before undoing the fastener on my lace top and letting it fall on the floor.

I told the lads to sit on the bed, and I sat between them. I started wanking both of them together, slowly at first and then faster and faster. Both cocks were as stiff as pokers, so I got on my knees and started giving head. I sucked on each cock for twenty seconds at a time, while continuing to wank the other. They were almost at bursting point when I decided to try to up the ante slightly.

"Forty euros more and you can both fuck Katya, yes?"

They both said, "Yes," so I stopped giving head and climbed back on the bed. One of the lads entered my pussy from behind, while I continued giving head to the other. After a couple of minutes, the lad who was fucking me shot his load into the condom. I remember feeling very pleased with myself because I'd handled my first trick so well.

The first lad withdrew his cock from my pussy, and the other one asked me to lie on my back on the bed. He got between my legs, and I guided his cock inside. I lifted my legs high as he fucked me, trying to draw his cock deeper. I told him to fuck me harder, and he did his best, but only lasted a few more seconds

He moaned loudly, and then I felt his warm seed fill the condom. He flopped down on top of me as his balls emptied. He was completely out of breath and was gasping. I waited until he got his breath back before clicking my fingers. He took the hint and climbed off me.

I collected both condoms and handed the lads a tissue to wipe their cocks on. Both condoms and tissues were then placed in a clinical waste bag, as Mariska had insisted.

I was given forty Euros, and then I opened the door to let the lads out. I allowed both of them to kiss me on the cheek before they left.

Now it was time to clean the room and change the bed sheet, before opening the curtain to await my next client.

I sat in my chair and as I read my book, I noticed a man who had walked past my window several times. I waited for him and, when he next appeared, I smiled at him and stood up. I opened the door, and he said that he was expecting to see Mariska and that he was a regular.

"Well, I'm Katya, and Mariska asked me to look after her clients tonight, because she didn't feel very well. Maybe I could help you out?"

"I'm Lucas. Mariska gives me a quickie fuck and charges me thirty Euros, but I'll come back when she's here."

He thanked me and went to walk off, but I told him to come in and that I would accept thirty.

I closed the curtains and handed Lucas a condom.

"Well, Lucas, how would you like to fuck me?"

"Turn round. Hands on bed. Take panties off."

I did as Lucas had asked, and he stood behind me, placing his hands on my hips. Then he pushed his hard cock inside my pussy and started fucking me very fast.

Lucas was grunting and gasping, and I almost started laughing, but thankfully, he didn't last long. He shot his hot spunk into the condom and pulled out of me within a couple of seconds. He handed me some banknotes and left without even removing the condom. The whole event had taken less than five minutes.

I tidied up, opened the curtains, and wondered who would be next.

Next turned out to be a well-dressed man in his early forties, who wanted a full sex for thirty minutes. He got totally naked for his session and managed to fuck me three times. He had paid me sixty Euros, and he certainly got his money's worth.

I did another tidy up and changed the bed sheet before taking a quick shower. Mariska had told me that she enjoyed working in the windows and that she loved to have sex. I enjoy sex too, but I like to choose who I have sex with, even if it's only a one-off. Mariska had her big house in a posh district and her high-end Mercedes car, and I wasn't trying to judge her.

The street on the other side of my window had become a lot busier. One of the women in a window on the other side of the street was dancing, while being watched by several men, who were encouraging her. Another girl was standing at her door, smoking a cigarette whilst talking to two men. She finished smoking, and all three went inside.

My next customers arrived a few minutes later. Two young men, called Michael and David, who both worked in Amsterdam, but were Welsh. I agreed to let both of them fuck me for 100 Euros.

Michael came in first and fucked me from behind until he came. It didn't take him long, and as he left, David entered. David wanted me to be his cowgirl, so he lay on the bed and I mounted him. I was honestly impressed by his cock. It was long, thick, and I knew it would feel good. As he fucked me, he enquired about Mariska. I explained about her tooth infection, and he asked me to pass his regards to her.

I let him fondle my breasts as he fucked me, and I didn't mind that he was taking longer to ride me than he had paid for. I even came very close to achieving an orgasm.

When David had finished using me, he told me that I gave a far better ride than Mariska. That was certainly a confidence booster. Then he pushed a twenty Euro note into my stocking tops as a tip before he left. Sometimes it feels good to be appreciated.

I did another thorough clean-up and took yet another quick shower before taking my seat back at the window. The street outside was much busier than before and a lot noisier too. A man tapped my window, and I opened my door to speak to him. He spoke in Dutch, and he stank of a mixture of alcohol and cannabis.

I shook my head from side to side, and he moved on quietly. I stood at the door for a few minutes and listened to the voices as people walked by. It seemed that the great majority of the people in the street were young British males who had either drunk too much alcohol or smoked too much weed.

A group of such young guys spotted me from across the street, and one of them shouted, "Hey, Missus, how much would you charge Sammy for a ride?"

A couple of Sammy's friends were egging him on, and I heard one of them say, "Go for it."

I closed the door and drew the curtains until they had moved on. When all was quiet, I opened the curtains again.

One of the young men from the boisterous...